build(deps): bump anchore/scan-action from 5 to 6

Bumps [anchore/scan-action](https://github.com/anchore/scan-action) from 5 to 6.
- [Release notes](https://github.com/anchore/scan-action/releases)
- [Changelog](https://github.com/anchore/scan-action/blob/main/CHANGELOG.md)
- [Commits](anchore/scan-action@v5...v6)

---
updated-dependencies:
- dependency-name: anchore/scan-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/security_scanning.yml

@@ -52,7 +52,7 @@ jobs:
             RUBYGEM_BUNDLER=${{ matrix.rubygem_bundler }}
 
       - name: Scan image with Anchore Grype
-        uses: anchore/scan-action@v5
+        uses: anchore/scan-action@v6
         id: scan
         with:
           image: 'ci/voxbox:${{ matrix.rubygem_puppet }}'